DESCRIPTION (investigator's abstract): Osteoporosis, one of the most common disorders in the elderly, results in over 1.5 million fractures of the hip, spine and other sites each year in the US. Early diagnosis and treatment of osteoporosis is vital to slow or stop bone loss, reduce fracture risk, and decrease disability and death. Our long-range goal is to devise a safe, effective, low-cost screening tool that can be used in a dental practice or public health clinic to identify patients likely to develop a fragility (osteoporotic) fracture. As over three-fourths of adults visit their dentist annually, the dental office is an ideal site for such screening. The objective of this application is to use dental radiographic features and clinical information to develop a statistical-based predictor of fracture risk. Our central hypothesis is that measurable changes in jawbone radiographic features predict patients who will develop osteoporotic fractures. We have found such changes in the maxilla and mandible of osteoporotic patients. We further hypothesize that risk factors differ between individuals with fracture and controls and that such patient-risk factors will provide additional discriminating data. Identification of key radiographic and clinical features associated with osteoporotic fracture will allow us to develop an efficient screening tool using radiographs routinely taken by dentists for other purposes. We are well prepared to undertake the proposed research because we have already measured radiographic features of the jaws in patients with osteoporosis. Further, we have data from the Leisure World Cohort Study, an elderly cohort (mean age = 85 years) of nearly 14,000 individuals that has been studied for 19 years. We propose a prospective cohort study using all subjects who entered the cohort with no history of adult fracture to evaluate radiographic and patient risk factors of those who develop fracture. To accomplish the goal of our project and test our hypothesis, we will pursue 3 specific aims: 1) identify and validate patient risk factors associated with osteoporotic fracture in the Leisure World Cohort, 2) identify morphologic features of dental radiographs associated with osteoporotic fracture, and 3) determine the optimum combination of radiographic and patient risk factors to quantify an individual's osteoporotic fracture risk as a function of time. We expect that as we found such radiographic changes in patients with osteoporosis, we will find comparable measurable features of the jawbones of patients who develop osteoporotic fractures. Similarly, we expect that these individuals can also be characterized by demographic and behavioral risk factors. We anticipate that these findings can be combined to form a safe, effective risk-assessment model for identifying patients at risk of osteoporotic fracture. This result will be significant because such a diagnostic screening tool would be applicable to a large fraction of the population at little expense and prevent needless morbidity and mortality.